blob: 809df77308ae17ab88c3cec508fe5a68e0081fe9 [file] [log] [blame]
// Copyright (c) 2015, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
#include "vm/log.h"
#include "vm/dart.h"
#include "vm/flags.h"
#include "vm/isolate.h"
#include "vm/thread.h"
namespace dart {
DEFINE_FLAG(bool, force_log_flush, false, "Always flush log messages.");
// The following flag is useful when debugging on Android, since
// adb logcat truncates messages that are "too long" (and always
// flushing would result in too many short messages).
DEFINE_FLAG(
int,
force_log_flush_at_size,
0,
"Flush log messages when buffer exceeds given size (disabled when 0).");
DEFINE_FLAG(charp,
isolate_log_filter,
nullptr,
"Log isolates whose name include the filter. "
"Default: service isolate log messages are suppressed "
"(specify 'vm-service' to log them).");
DEFINE_FLAG(charp,
redirect_isolate_log_to,
nullptr,
"Log isolate messages into the given file.");
namespace {
class LogFile {
public:
static const LogFile& Instance() {
static LogFile log_file;
return log_file;
}
static void Print(const char* data) {
Dart::file_write_callback()(data, strlen(data), Instance().handle_);
}
private:
LogFile()
: handle_(Dart::file_open_callback()(FLAG_redirect_isolate_log_to,
/*write=*/true)) {}
~LogFile() { Dart::file_close_callback()(handle_); }
void* handle_;
};
} // namespace
Log::Log(LogPrinter printer) : printer_(printer), manual_flush_(0), buffer_(0) {
if (printer_ == nullptr) {
if (FLAG_redirect_isolate_log_to == nullptr) {
printer_ = [](const char* data) { OS::PrintErr("%s", data); };
} else {
printer_ = &LogFile::Print;
}
}
}
Log::~Log() {
// Did someone enable manual flushing and then forgot to Flush?
ASSERT(cursor() == 0);
}
Log* Log::Current() {
Thread* thread = Thread::Current();
if (thread == nullptr) {
OSThread* os_thread = OSThread::Current();
ASSERT(os_thread != nullptr);
return os_thread->log();
}
IsolateGroup* isolate_group = thread->isolate_group();
if ((isolate_group != nullptr) &&
Log::ShouldLogForIsolateGroup(isolate_group)) {
OSThread* os_thread = thread->os_thread();
ASSERT(os_thread != nullptr);
return os_thread->log();
} else {
return Log::NoOpLog();
}
}
void Log::Print(const char* format, ...) {
if (this == NoOpLog()) {
return;
}
va_list args;
va_start(args, format);
VPrint(format, args);
va_end(args);
}
void Log::VPrint(const char* format, va_list args) {
if (this == NoOpLog()) {
return;
}
// Measure.
va_list measure_args;
va_copy(measure_args, args);
intptr_t len = Utils::VSNPrint(nullptr, 0, format, measure_args);
va_end(measure_args);
// Print.
char* buffer = reinterpret_cast<char*>(malloc(len + 1));
va_list print_args;
va_copy(print_args, args);
Utils::VSNPrint(buffer, (len + 1), format, print_args);
va_end(print_args);
// Append.
// NOTE: does not append the '\0' character.
for (intptr_t i = 0; i < len; i++) {
buffer_.Add(buffer[i]);
}
free(buffer);
if (ShouldFlush()) {
Flush();
}
}
void Log::Flush(const intptr_t cursor) {
if (this == NoOpLog()) {
return;
}
if (buffer_.is_empty()) {
return;
}
if (buffer_.length() <= cursor) {
return;
}
TerminateString();
const char* str = &buffer_[cursor];
ASSERT(str != nullptr);
printer_(str);
buffer_.TruncateTo(cursor);
}
void Log::Clear() {
if (this == NoOpLog()) {
return;
}
buffer_.TruncateTo(0);
}
intptr_t Log::cursor() const {
return buffer_.length();
}
bool Log::ShouldLogForIsolateGroup(const IsolateGroup* isolate_group) {
if (FLAG_isolate_log_filter == nullptr) {
if (IsolateGroup::IsSystemIsolateGroup(isolate_group)) {
// By default, do not log for the service or kernel isolates.
return false;
}
return true;
}
const char* name = isolate_group->source()->name;
ASSERT(name != nullptr);
if (strstr(name, FLAG_isolate_log_filter) == nullptr) {
// Filter does not match, do not log for this isolate.
return false;
}
return true;
}
Log Log::noop_log_;
Log* Log::NoOpLog() {
return &noop_log_;
}
void Log::TerminateString() {
if (this == NoOpLog()) {
return;
}
buffer_.Add('\0');
}
void Log::EnableManualFlush() {
if (this == NoOpLog()) {
return;
}
manual_flush_++;
}
void Log::DisableManualFlush(const intptr_t cursor) {
if (this == NoOpLog()) {
return;
}
manual_flush_--;
ASSERT(manual_flush_ >= 0);
if (manual_flush_ == 0) {
Flush(cursor);
}
}
bool Log::ShouldFlush() const {
#ifdef DART_TARGET_OS_ANDROID
// Android truncates on 1023 characters, flush more eagerly.
// Flush on newlines, because otherwise Android inserts newlines everywhere.
if (*(buffer_.end() - 1) == '\n') {
return true;
}
#endif // DART_TARGET_OS_ANDROID
return ((manual_flush_ == 0) || FLAG_force_log_flush ||
((FLAG_force_log_flush_at_size > 0) &&
(cursor() > FLAG_force_log_flush_at_size)));
}
void LogBlock::Initialize() {
log_->EnableManualFlush();
}
LogBlock::~LogBlock() {
log_->DisableManualFlush(cursor_);
}
} // namespace dart